Loan repayment with bonus

Separate regular monthly and bonus repayment principals, and calculate with the exact elapsed months until the first bonus month.

If calculation UI does not appear, reload with JavaScript enabled. Related context links below remain available.

Calculation specification

Reviewed on:

Formula basis

Regular principal equals total principal minus bonus principal and is amortized monthly. Bonus principal is amortized in the selected pair of months, with interest accrued for the actual elapsed months since the prior bonus reference month.

Calculation method

Splits total borrowing into a regular monthly principal and a bonus principal, then combines monthly payments with semiannual bonus payments in one schedule.

Exclusions and checks required

  • Bonus months are limited to the three month pairs offered by the form, and bonus income is assumed constant.
  • Rate changes, rounding, and final-balance adjustment follow this calculator's monthly model and may differ from a lender's contract.

Example input:：Allocating JPY 6 million of a JPY 30 million loan to bonus payments

principalMan
3000
bonusPrincipalMan
600
method
annuity
rounding
floor
initialRate
1.5
initialYears
35
laterRate
1.5
termYears
35
termMonths
0
bonusPair
6,12
startMonth
2026-07

The first bonus interest depends on elapsed months and does not guarantee a lender's bonus installment.

FAQ

Who is this calculator for? Loan repayment with bonus

Separate regular monthly and bonus repayment principals, and calculate with the exact elapsed months until the first bonus month.

What values should I enter?

Applies to: Loan repayment / Monthly and bonus repayments are calculated as separate principal streams, with interest accrued month-by-month.

How should I interpret this estimate?

Splits total borrowing into a regular monthly principal and a bonus principal, then combines monthly payments with semiannual bonus payments in one schedule.

How to use

  1. Enter your input values and press Calculate.
  2. Review the result and compare it with expected context.
  3. Regular principal equals total principal minus bonus principal and is amortized monthly. Bonus principal is amortized in the selected pair of months, with interest accrued for the actual elapsed months since the prior bonus reference month.